Process for preparing di(fluoroalkyl containing group-substituted alkyl) phosphate salt

ABSTRACT

A di(fluoroalkyl containing group-substituted alkyl) phosphate salt which is useful for a surface active agent, a water- and/or oil-repellent for fiber or paper or an oil resistant agent, can be prepared a process which comprises hydrolyzing a mono-sec.- or tert.-alkyl (di(fluoroalkyl containing group-substituted alkyl) phosphate with a base.

This is a continuation-in-part application of Ser. No. 07/184,673 filedon Apr. 22, 1988, now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a process for preparing adi(fluoroalkyl containing group-substituted alkyl) phosphate salt.

The di(fluoroalkyl containing group-substituted alkyl) phosphate salt isuseful as a surface active agent, a water- and/or oil-repellent forfiber or paper or an oil resistant agent.

2. Description of the Related Art

Processes for preparing fluoroalkyl containing group-substituted alkylphosphate esters are disclosed in, for example, Japanese PatentPublications Nos. 7776/1979, 29875/1981 and 48158/1982 and JapanesePatent Kokai Publication No. 64990/1985.

However, the phosphate esters which are obtained by the above processeshave wide distribution of composition which contains two or three of amonoalkyl ester, a dialkyl ester and a trialkyl ester. Of these threeesters, the di(fluoroalkyl containing group-substituted alkyl) phosphateester has the highest oil resistance, but is not produced in a highselectivity and contains relatively large amounts of monoalkyl andtrialkyl esters. A yield of dialkyl esters is at most about 80% byweight, as described in Examples of Japanese Patent Publication No.7776/1979. It is desired to increase the selectivity of dialkyl esters.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a process for preparinga fluoroalkyl containing group-substituted alkyl phosphate ester bywhich a dialkyl ester is produced in a high selectivity.

This and other objects of the present invention are achieved by aprocess for preparing a di(fluoroalkyl containing group-substitutedalkyl) phosphate salt which comprises hydrolyzing a mono-sec.- ortert.-alkyl di(fluoroalkyl containing group-substituted alkyl) phosphatewith a base.

DETAILED DESCRIPTION OF THE INVENTION

Illustrative types of the di(fluoroalkyl containing group-substitutedalkyl) phosphate salt produced by the process according to the presentinvention are of the formula:

    [R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --O].sub.2 PO--OA.sup.2(I)

wherein each R_(f) is independently a perfluoroalkyl group orω-hydroperfluoroalkyl group having 3 to 21 carbon atoms,

each A¹ is independently a divalent group which bonds R_(f) to--(CH₂)_(m) --,

A² is an alkaline metal or an ammonium group which may be substitutedwith an alkyl and/or hydroxyalkyl group,

k is 0 or 1, and

m is an integer of 1 to 4.

R_(f) in the formula (I) may be linear, branched, cyclic (for example,perfluorocyclohexyl) or combination thereof.

A¹ is, for example, --COO--, --SO₂, --O--, --(CH₂)₃ --O--, --S--,--(CH₂)_(p) --NR'--, --CH₂ CH(OR')--, --CO--NR'-- or --SO₂ --NR' inwhich R' is a hydrogen or an alkyl group having 1 to 5 carbon atoms andp is an integer of 1 to 6.

Specific examples of the di(fluoroalkyl containing group-substitutedalkyl) phosphate salt of the formula (I) are:

(C₄ F₉ CH₂ CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂

[(CF₃)₂ CF(CF₂)₆ CH₂ CH₂ O]₂ POONH₂ (C₂ H₄ OH)₂

(C₈ F₁₇ CH₂ CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂

(C₆ F₁₃ CH₂ CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂

(C₁₀ F₂₁ CH₂ CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂

(C₁₂ F₂₅ CH₂ CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂

(C₁₄ F₂₉ CH₂ CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂

(C₈ F₁₇ CH₂ CH₂ O)₂ POONH₄

(C₈ F₁₇ CH₂ CH₂ O)₂ POONH(C₂ H₄ OH)₃

[C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₄

[C₆ F₁₃ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₄

[C₁₀ F₂₁ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₄

[C₁₂ F₂₅ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₄

[C₁₄ F₂₉ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₄

[C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₂ (CH₂ CH₂ OH)₂

[C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH(CH₂ CH₂ OH)₃

[C₈ F₁₇ SO₂ N(C₃ H₇)CH₂ CH₂ O]₂ POONH₂ (CH₂ CH₂ OH)₂

[C₈ F₁₇ CON(C₂ H₅)CH₂ CH₂ O]₂ POONH(CH₂ CH₂ OH)₃

(C₈ F₁₇ COOCH₂ CH₂ O)₂ POONH₄

(C₈ F₁₇ SO₂ CH₂ CH₂ O)₂ POONH₄

[C₈ F₁₇ (CH₂)₃ OCH₂ CH₂ O]₂ POONH₄

[C₈ F₁₇ CH₂ CH(OH)CH₂ O]₂ POONH₄

To prepare the di(fluoroalkyl containing group-substituted alkyl)phosphate salt of the formula (I), an alkyl ester of di(fluoroalkylcontaining group-substituted alkyl) phosphate is hydrolyzed with a base.The alkyl ester of di(fluoroalkyl containing group-substituted alkyl)phosphate is preferably of the formula:

    [R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --O].sub.2 PO--OR(II)

wherein R is a secondary or tertiary alkyl or alkenyl group having 3 to9 carbons, and R_(f), A¹, k and m are the same as defined above. Analcoholic residue which is formed by the secondary or tertiary alkyl oralkenyl group is easily removed by hydrolysis to form the diesterphosphate salt of the formula (I).

Specific examples of the alkyl ester of di(fluoroalkyl containinggroup-substituted alkyl) phosphate of the formula (II) are:

(C₄ F₉ CH₂ CH₂ O)₂ POOCH(CH₃)₂

[(CF₃)₂ CF(CF₂)₆ CH₂ CH₂ O]₂ POOCH(CH₃)₂

(C₈ F₁₇ CH₂ CH₂ O)₂ POOCH(CH₃)₂

(C₆ F₁₃ CH₂ CH₂ O)₂ POOCH(CH₃)₂

(C₁₀ F₂₁ CH₂ CH₂ O)₂ POOCH(CH₃)₂

(C₁₂ F₂₅ CH₂ CH₂ O)₂ POOCH(CH₃)₂

(C₁₄ F₂₉ CH₂ CH₂ O)₂ POOCH(CH₃)₂

(C₈ F₁₇ CH₂ CH₂ O)₂ POOC(CH₃)₃

(C₈ F₁₇ CH₂ CH₂ O)₂ POOCH₂ CH₂ CH(CH₃)₂

[C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂

[C₆ F₁₃ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂

[C₁₀ F₂₁ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂

[C₁₂ F₂₅ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂

[C₁₄ F₂₉ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂

[C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOC(CH₃)₃

[C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOCH₂ CH₂ CH(CH₃)₂

[C₈ F₁₇ SO₂ N(C₃ H₇)CH₂ CH₂ O]₂ POOCH(CH₃)₂

[C₈ F₁₇ CON(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂

[C₈ F₁₇ COOCH₂ CH₂ O]₂ POOCH(CH₃)₂

[C₈ F₁₇ SO₂ CH₂ CH₂ O]₂ POOCH(CH₃)₂

[C₈ F₁₇ (CH₂)₃ OCH₂ CH₂ O]₂ POOCH₂ CH(CH₃)₂

[C₈ F₁₇ CH₂ CH(OH)CH₂ O]₂ POOCH(CH₃)₂

The base which is used to hydrolyze the alkyl ester of di(fluoroalkylcontaining group-substituted alkyl) phosphate of the formula (II) ispreferably an alkali hydroxide, an ammonium hydroxide or an amine.Examples of the alkali hydroxide are potassium hydroxide and sodiumhydroxide. Examples of the amine are trimethylamine, triethylamine,tripropylamine, tributylamine, triethanolamine, diethylamine,dipropylamine, diethanolamine, ethylamine, propylamine and ethanolamine.

The hydrolysis can be carried out by adding ammonium hydroxide or anamine/water mixture, or an alkali hydroxide/alcohol/water mixture to thealkyl ester of di(fluoroalkyl containing group-substituted alkyl)phosphate. The alcohol which is used in hydrolysis includes a secondaryor tertiary C₃ -C₆ alcohol such as isopropyl alcohol, tert.-butylalcohol, sec.-butyl alcohol, tert.-amyl alcohol, isoamyl alcohol andsec.-amyl alcohol.

The base is used in an amount of at least one equivalent, preferably 1to 10 equivalents per mole of the alkyl di(fluoroalkyl containinggroup-substituted alkyl) phosphate.

The pressure during hydrolysis is not critical. Usually, the hydrolysisis carried out under an atmospheric pressure at a temperature of 80° to100° C. for 2 to 6 hours.

The alkyl ester of di(fluoroalkyl containing group-substituted alkyl)phosphate of the formula (II) can be prepared by reacting a fluoroalkylcontaining group-substituted alcohol of the formula:

    R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --OH            (III)

wherein R_(f), A¹, k and m are the same as defined above, with aphosphoryl monoalkoxide dihalide of the formula:

    RO--POX.sub.2                                              (IV)

wherein each X is independently halogen atom, for example, chlorine orbromine and R is the same as defined above.

Specific examples of the alcohol of the formula (III) are:

C₄ F₉ CH₂ CH₂ OH

(CF₃)₂ CF(CF₂)₆ CH₂ CH₂ OH

C₈ F₁₇ CH₂ CH₂ OH

C₁₀ F₂₁ CH₂ CH₂ OH

C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ OH

C₈ F₁₇ SO₂ N(C₃ H₇)CH₂ CH₂ OH

C₈ F₁₇ SO₂ N(CH₃)CH₂ CH₂ OH

In the reaction, a molar ratio of the alcohol of the formula (III) tothe phosphoryl monoalkoxide dihalide of the formula (IV) is preferablyfrom 2:1 to 2:1.2. The reaction pressure is not critial. Usually, thereaction is carried out under an atmospheric pressure at 80° to 100° C.for 2 to 4 hours.

The phosphoryl monoalkoxide dihalide of the formula (IV) can be preparedby reacting a secondary or tertiary alcohol of the formula:

    ROH                                                        (V)

wherein R is the same as defined above, with a phosphoryl trihalide ofthe formula:

    POX.sub.3                                                  (VI)

wherein X is the same as defined above.

It is not preferable to use a primary alcohol instead of the secondaryor tertiary alcohol of the formula (V), since the alkyl ester ofdi(fluoroalkyl containing group-substituted alkyl) phosphate of theformula (II) is hardly hydrolyzed.

As the phosphoryl trihalide of the formula (VI), usually phosphoryltrichloride is used because of its availability, although phosphoryltribromide and phosphoryl bromide chloride may be used.

A molar ratio of the secondary or tertiary alcohol of the formula (V) tothe phosphoryl trihalide of the formula (VI) is preferably about 1:1,preferably 0.9:1 to 1:1. The reaction pressure is not critical. Usually,the reaction is carried out under an atmospheric pressure at atemperature of room temperature (e.g. 20° C.) to 70° C. for 2 to 4hours.

Therefore, the di(fluoroalkyl containing group-substituted alkyl)phosphate salt of the formula (I) can be prepared by reacting thesecondary or tertiary alcohol of the formula (V) with the phosphoryltrihalide of the formula (VI) to produce the phosphoryl monoalkoxidedihalide of the formula (IV), reacting the phosphoryl monoalkoxidehalide of the formula (IV) with the fluoroalkyl containinggroup-substituted alcohol of the formula (III) to produce the alkylester of di(fluoroalkyl containing group-substituted alkyl) phosphate ofthe formula (II), and hydrolyzing the alkyl ester of di(fluoroalkylcontaining group-substituted alkyl) phosphate of the formula (II) withthe base.

According to the present invention, the di(fluoroalkyl containinggroup-substituted alkyl) phosphate salt can be prepared in a purity ofnot less than 90% by weight.

The present invention will be explained further in detail by thefollowing Examples.

EXAMPLE 1

In a 200 ml flask equipped with a stirrer, a Dimroth condenser and adropping funnel, phosphoryl trichloride (154 g, 1 mol) was charged andisopropyl alcohol (57 g, 0.95 mol) was dropwise added over 30 minuteswith stirring. The reaction was exothermic and hydrogen chloride gasevolved. After completing the exothermic reaction, the reaction mixturewas heated at 70° C. for one hour to give a colorless liquid mixturecontaining POCl₃ (1 g), C₃ H₇ OPOCl₂ (175 g) and (C₃ H₇ O)₂ POCl (3 g).

In a one liter flask, a compound (200 g, 0.39 mol) of the formula:

    C.sub.n F.sub.n+1 CH.sub.2 CH.sub.2 OH

wherein molar fractions of compounds which have n of 8, 10, 12, 14 and16 respectively are 55, 26, 12, 5 and 2, was charged. While atemperature was maintained at 80° C., the resultant liquid mixture (37g) in the above was added with stirring. Hydrogen chloride evolved andthe reaction started. The reaction mixture was heated to 95° C. andstirred for 2 hours. Then, water (1.5 g) was added and the reactionmixture was stirred for 2 hours to give a mixture of the followingcomposition:

Diisopropyl mono(fluoroalkyl containing group-substituted alkyl)phosphate: 5% by weight

Monoisopropyl di(fluoroalkyl containing group-substituted alkyl)phosphate: 93% by weight

Tri(fluoroalkyl containing group-substituted phosphate: 2% by weight

The mixture contained no ester having a chlorine atom.

Diethanolamine (65 g) as a hydrolyzing agent was added to the mixture.The mixture was stirred at 95° C. for 3 hours. After cooling, a wax-likesolid was obtained. Yield: 297 g. The final product was analyzed by ³¹P-NMR spectrum to determine its composition. The result is shown in theTable.

EXAMPLE 2

A wax-like solid was obtained in the same manner as in Example 1 butusing tert.-butyl alcohol (70.3 g, 0.95 mol) in place of isopropylalcohol. Yield: 302 g. A composition of the final product is shown inthe Table.

EXAMPLE 3

A wax-like solid was obtained in the same manner as in Example 1 butusing tert.-amyl alcohol (83.6 g, 0.95 mol) in place of isopropylalcohol. Yield: 315 g. A composition of the final product is shown inthe Table.

EXAMPLE 4

An aqueous solution was obtained in the same manner as in Example 1 butusing sodium hydroxide (20 g) and methyl alcohol (100 g) in place ofdiethanolamine. Yield: 352 g. A composition of the final product isshown in the Table.

EXAMPLE 5

A wax-like solid was obtained in the same manner as in Example 1 butusing diethylamine (30 g) in place of diethanolamine. Yield: 262 g. Acomposition of the final product is shown in the Table.

EXAMPLE 6

In a 200 ml flask equipped with a stirrer, a Dimroth condenser and adropping funnel, phosphoryl trichloride (154 g, 1 mol) was charged andisopropyl alcohol (57 g, 0.95 mol) was dropwise added over 30 minuteswith stirring. The reaction was exothermic and hydrogen chloride gasevolved. After completing the exothermic reaction, the reaction mixturewas heated at 70° C. for one hour to give a colorless liquid mixturecontaining POCl₃ (1 g), C₃ H₇ OPOCl₂ (175 g) and (C₃ H₇ O)₂ POCl (3 g).

In a one liter flask, a compound (280 g, 0.39 mol) of the formula:

    C.sub.8 F.sub.17 SO.sub.2 N(C.sub.2 H.sub.5)CH.sub.2 CH.sub.2 OH

was charged. While a temperature was kept at 80° C., the resultantliquid mixture (37 g) in the above was added with stirring. Hydrogenchloride evolved and the reaction started. The reaction mixture washeated to 95° C. and stirred for 2 hours. Then, water (1.5 g) was addedand the reaction mixture was stirred for 2 hours to give a mixture ofthe following composition:

Diisopropyl mono(fluoroalkyl containing group-substituted alkyl)phosphate: 4% by weight

Monoisopropyl di(fluoroalkyl containing group-substituted alkyl)phosphate: 95% by weight

Tri(fluoroalkyl containing group-substituted alkyl) phosphate: 1% byweight

The mixture contained no ester having chlorine atom.

Diethanolamine (65 g) as a hydrolyzing agent was added to the mixture.The mixture was stirred at 95° C. for 3 hours. After cooling, a wax-likesolid was obtained. Yield: 373 g. The final product was analyzed by ³¹P-NMR spectrum to determine its composition. The result is shown in theTable.

                  TABLE                                                           ______________________________________                                        Example  Composition (% by weight)                                            No.      Monoester.sup.1                                                                              Diester.sup.2                                                                          Triester.sup.3                               ______________________________________                                        1        5              93       2                                            2        4              92       4                                            3        5              92       3                                            4        5              95       0                                            5        3              92       5                                            6        4              95       1                                            ______________________________________                                         Note:                                                                         .sup.1 Monoester is a mono(fluoroalkyl containing groupsubstituted alkyl)     phosphate salt.                                                               .sup.2 Diester is a di(fluoroalkyl containing groupsubstituted alkyl)         phosphate salt which is a desired compound according to the present           invention.                                                                    .sup.3 Triester is a tri(fluoroalkyl containing groupsubstituted alkyl)       phosphate.                                                               

In the above Examples, the di(fluoroalkyl containing group-substitutedalkyl) phosphate salts are di(2-perfluoroalkyl-ethyl) phosphate salt anddi(N-ethyl perfluoroalkanesulfonamidoethyl) phosphate salt. However, itis obvious for those skilled in the art to prepare other di(fluoroalkylcontaining group-substituted alkyl) phosphate salts in the same manneras in the Examples. Although the Examples show the processes usingdiethanolamine, sodium hydroxide or diethylamine as the base, it is alsoobvious to use other bases since a hydrolysis reaction can be carriedout with any base.

What is claimed is:
 1. A process for preparing a di(fluoroalkylcontaining group-substituted alkyl) phosphate salt of the formula:

    [R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --O].sub.2 PO--OA.sup.2(I)

which comprises hydrolyzing a mon-sec. or tert.-alkyl or alkenyldi(fluoroalkyl containing group-substituted alkyl) phosphate of theformula:

    [R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --O].sub.2 PO--OR(II)

with a base selected from the group consisting of an alkali hydroxide,an ammonium hydroxide and an amine, at a temperature of 80° to 100° C.,the base being used in an amount of 1 to 10 equivalents per mole of thealkyl or alkenyl di(fluoroalkyl containing group-substituted alkyl)phosphate (II), wherein each R_(f) is independently a perfluoroalkylgroup or ω-hydroperfluoroalkyl group having 3 to 21 carbon atoms and maybe linear, branched, cyclic or a combination thereof, each A¹ isindependently a divalent group which is selected from the groupconsisting of --COO--, SO₂ --, --O--, --(CH₂)₃ --O--, --S--, --(CH₂)_(p)--NR'--, --CH₂ CH(OR')--, --CO--NR'-- or --SO₂ --NR'--in which R' is ahydrogen or an alkyl group having 1 to 5 carbon atoms, and p is ainteger of 1 to 6, A² is an alkaline metal or an ammonium group whichmay be substituted with an alkyl and/or hydroxyalkyl group, R is asecondary or tertiary alkyl or alkenyl group having 3 to 9 carbon atoms,k is 0 to 1, and m is an integer of 1 to
 4. 2. The process of claim 1,wherein the di(fluoroalkyl containing group-substituted alkyl) phosphatesalt of formula (I) is selected from the group consisting of:(C₄ F₉ CH₂CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂ [(CF₃)₂ CF(CF₂)₆ CH₂ CH₂ O]₂ POONH₂ (C₂ H₄OH)₂ (C₈ F₁₇ CH₂ CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂ (C₆ F₁₃ CH₂ CH₂ O)₂ POONH₂(C₂ H₄ OH)₂ (C₁₀ F₂₁ CH₂ CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂ (C₁₂ F₂₅ CH₂ CH₂ O)₂POONH₂ (C₂ H₄ OH)₂ (C₁₄ F₂₉ CH₂ CH₂ O)₂ POONH₂ (C₂ H₄ OH)₂ (C₈ F₁₇ CH₂CH₂ O)₂ POONH₄ (C₈ F₁₇ CH₂ CH₂ O)₂ POONH(C₂ H₄ OH)₃ [C₈ F₁₇ SO₂ N(C₂H₅)CH₂ CH₂ O]₂ POONH₄ [C₆ F₁₃ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₄ [C₁₀ F₂₁SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₄ [C₁₂ F₂₅ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₄[C₁₄ F₂₉ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH₄ [C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂POONH₂ (CH₂ CH₂ OH)₂ [C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POONH(CH₂ CH₂ OH)₃[C₈ F₁₇ SO₂ N(C₃ H₇)CH₂ CH₂ O]₂ POONH(CH₂ CH₂ OH)₂ [C₈ F₁₇ CON(C₂ H₅)CH₂CH₂ O]₂ POONH(CH₂ CH₂ OH)₃ (C₈ F₁₇ COOCH₂ CH₂ O)₂ POONH₄ (C₈ F₁₇ SO₂ CH₂CH₂ O)₂ POONH₄ [C₈ F₁₇ (CH₂)₃ OCH₂ CH₂ O]₂ POONH₄, and [C₈ F₁₇ CH₂CH(OH)CH₂ O]₂ POONH₄.
 3. The process of claim 1, wherein the alkyl esterof the di(fluoro-alkyl containing group substituted alkyl) phosphate offormula (II) is selected from the group consisting of:(C₄ F₉ CH₂ CH₂ O)₂POOCH(CH₃)₂ [(CF₃)₂ CF(CF₂)₆ CH₂ CH₂ O]₂ POOCH(CH₃)₂ (C₈ F₁₇ CH₂ CH₂ O)₂POOCH(CH₃)₂ (C₆ F₁₃ CH₂ CH₂ O)₂ POOCH(CH₃)₂ (C₁₀ F₂₁ CH₂ CH₂ O)₂POOCH(CH₃)₂ (C₁₂ F₂₅ CH₂ CH₂ O)₂ POOCH(CH₃)₂ (C₁₄ F₂₉ CH₂ CH₂ O)₂POOCH(CH₃)₂ (C₈ F₁₇ CH₂ CH₂ O)₂ POOC(CH₃)₃ (C₈ F₁₇ CH₂ CH₂ O)₂ POOCH₂CH₂ CH(CH₃)₂ [C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂ [C₆ F₁₃ SO₂N(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂ [C₁₀ F₂₁ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂POOCH(CH₃)₂ [C₁₂ F₂₅ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂ [C₁₄ F₂₉ SO₂N(C₂ H₅)CH₂ CH₂ O]₂ POOCH(CH₃)₂ [C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂POOCH(CH₃)₃ [C₈ F₁₇ SO₂ N(C₂ H₅)CH₂ CH₂ O]₂ POOCH₂ CH₂ CH(CH₃)₂ [C₈ F₁₇SO₂ N(C₃ H₇)CH₂ CH₂ O]₂ POOCH(CH₃)₂ [C₈ F₁₇ CON(C₂ H₅)CH₂ CH₂ O]₂POOCH(CH₃)₂ [C₈ F₁₇ COOCH₂ CH₂ ]₂ POOCH(CH₃)₂ [C₈ F₁₇ SO₂ CH₂ CH₂ O]₂POOCH(CH₃)₂ [C₈ F₁₇ (CH₂)OCH₂ CH₂ O]₂ POOCH₂ CH(CH₃)₂, and [C₈ F₁₇ CH₂CH(OH)CH₂ O]₂ POOCH(CH₃)₂.
 4. The process of claim 1, wherein the alkalihydroxide is selected from the group consisting of potassium hydroxideand sodium hydroxide.
 5. The process of claim 1, wherein the amine isselected from the group consisting of trimethylamine, triethylamine,tripropylamine, tributylamine, triethanolamine, diethylamine,dipropylamine, diethanolamine, ethylamine, propylamine and ethanolamine.6. The process of claim 4, wherein the alcohol of formula (III) isselected from the group consisting of:C₄ F₉ CH₂ CH₂ OH (CF₃)₂ CF(CF₂)₆CH₂ CH₂ OH C₈ F₁₇ CH₂ CH₂ OH C₁₀ F₂₁ CH₂ CH₂ OH C₈ F₁₇ SO₂ N(C₂ H₅)CH₂CH₂ OH C₈ F₁₇ SO₂ N(C₃ H₇)CH₂ CH₂ OH, and C₈ F₁₇ SO₂ N(CH₃)CH₂ CH₂ OH.7. The process according to claim 4, wherein the molar ratio of thealcohol of formula (III) to the phosphoryl monoalkoxide dihalide offormula (IV) is 2:1 to 2:1.2.
 8. The process of claim 1, wherein thebase is selected from the group consisting of diethanolamine, sodiumhydroxide and diethylamine.
 9. A process for preparing a di(fluoroalkylcontaining group-substituted alkyl) phosphate salt of formula (I)

    [R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --O].sub.2 PO--OA.sup.2(I)

which comprises: reacting a secondary or tertiary alcohol withphosphoryl trihalide in a molar ratio of the secondary or tertiaryalcohol to the phosphoryl trihalide of 0.9:1 to 1:1 at a temperature ofroom temperature to 70° C. to produce a phosphoryl monoalkoxidedihalide, reacting the phosphoryl monoalkoxide dihalide with afluoroalkyl containing group-substituted alcohol in a molar ratio ofsaid dihalide to the fluoroalkyl containing group-substituted alcohol of1:2 to 1.2:2 at a temperature of 80° to 100° C. to produce a mono sec.-or tert.-alkyl di(fluoroalkyl containing group-substituted alkyl)phosphate of formula (II)

    [R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --O].sub.2 PO--OR(II)

and hydrolyzing the mono-sec.- or tert.-alkyl di(fluoroalkyl containinggroup-substituted alkyl) phosphate of formula (II) with a base at atemperature of 80° to 100° C., the base being used in an amount of 1 to10 equivalent per mole of the alkyl or alkenyl di(fluoroalkyl containinggroup-substituted alkyl) phosphate of formula (II), wherein each R_(f)is independently a perfluoroalkyl group or ω-hydroperfluoroalkyl grouphaving 3 to 21 carbon atoms and may be linear, branched, cyclic or acombination thereof, each A¹ is independently a divalent group which isselected from the group consisting of --COO--, SO₂ --, --O--, --(CH₂)₃--O--, --S--, --(CH₂)_(p) --NR'--, --CH₂ CH(OR')--, --CO--NR'-- or --SO₂--NR'-- in which R' is a hydrogen or an alkyl group having 1 to 5 carbonatoms, and p is a integer of 1 to 6, A² is an alkaline metal or anammonium group which may be substituted with an alkyl and/orhydroxyalkyl group, R is a secondary or tertiary alkyl or alkenyl grouphaving 3 to 9 carbon atoms, k is 0 to 1, and m is an integer of 1 to 4.10. A process for preparing a di(fluoroalkyl containinggroup-substituted alkyl) phosphate salt of the formula:

    [R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --O].sub.2 PO--OA.sup.2(I)

which comprises reacting a secondary or tertiary alcohol of the formula:

    ROH                                                        (V)

with a phosphoryl trihalide of the formula:

    POX.sub.3                                                  (VI)

in a molar ratio of the secondary or tertiary alcohol to the phosphoryltrihalide of 0.9:1 to 1:1 at a temperature of room temperature to 70° C.to produce a phosphoryl monoalkoxide dihalide of the formula:

    RO--POX.sub.2                                              (IV)

and reacting the phosphoryl monoalkoxide dihalide of the formula (IV)with a fluoroalkyl containing group-substituted alcohol of the formula:

    R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --OH            (III)

in a molar ratio of said dihalide to the fluoroalkyl containinggroup-substituted alcohol of 1:2 to 1.2:2 at a temperature of 80° to100° C. to produce an alkyl ester of di(fluoroalkyl containinggroup-substituted alkyl) phosphate of the formula:

    [R.sub.f --A.sup.1.sub.k --(CH.sub.2).sub.m --O].sub.2 PO--OR(II)

and then hydrolyzing the alkyl ester of di(fluoroalkyl containinggroup-substituted alkyl) phosphate of the formula (II) with a baseselected from the group consisting of an alkali hydroxide, an ammoniumhydroxide and an amine, at a temperature of 80° to 100° C., the basebeing used in an amount of 1 to 10 equivalent per mole of the alkyl oralkenyl di(fluoroalkyl containing group-substituted alkyl) phosphate offormula (II), wherein each R_(f) is independently a perfluoroalkyl groupor ω-hydroperfluoroalkyl group having 3 to 21 carbon atoms, each A¹ isindependently a divalent group which is selected from the groupconsisting of --COO--, SO₂ --, --O--, --(CH₂)₃ --O--, --S--, --(CH₂)_(p)--NR'--, --CH₂ CH(OR')--, --CO--NR'-- or --SO₂ --NR'-- in which R' is ahydrogen or an alkyl group having 1 to 5 carbon atoms, and p is ainteger of 1 to 6, A² is an alkaline metal or an ammonium group whichoptionally have an alkyl and/or hydroxyalkyl substituent, R is asecondary or tertiary alkyl or alkenyl group having 3 to 9 carbons, eachX is independently halogen, k is 0 to 1, and m is an integer of 1 to 4.